/* Copyright (c) 2017 Facebook * * This program is free software; you can redistribute it and/or * modify it under the terms of version 2 of the GNU General Public * License as published by the Free Software Foundation. */#include <linux/slab.h>#include <linux/bpf.h> #include "map_in_map.h" struct bpf_map *bpf_map_meta_alloc(int inner_map_ufd){	struct bpf_map *inner_map, *inner_map_meta;	struct fd f; 	f = fdget(inner_map_ufd);	inner_map = __bpf_map_get(f);	if (IS_ERR(inner_map))		return inner_map; 	/* prog_array->owner_prog_type and owner_jited	 * is a runtime binding.  Doing static check alone	 * in the verifier is not enough.	 */	if (inner_map->map_type == BPF_MAP_TYPE_PROG_ARRAY) {		fdput(f);		return ERR_PTR(-ENOTSUPP);	} 	/* Does not support >1 level map-in-map */	if (inner_map->inner_map_meta) {		fdput(f);		return ERR_PTR(-EINVAL);	} 	inner_map_meta = kzalloc(sizeof(*inner_map_meta), GFP_USER);	if (!inner_map_meta) {		fdput(f);		return ERR_PTR(-ENOMEM);	} 	inner_map_meta->map_type = inner_map->map_type;	inner_map_meta->key_size = inner_map->key_size;	inner_map_meta->value_size = inner_map->value_size;	inner_map_meta->map_flags = inner_map->map_flags;	inner_map_meta->ops = inner_map->ops;	inner_map_meta->max_entries = inner_map->max_entries; 	fdput(f);	return inner_map_meta;} void bpf_map_meta_free(struct bpf_map *map_meta){	kfree(map_meta);} bool bpf_map_meta_equal(const struct bpf_map *meta0,			const struct bpf_map *meta1){	/* No need to compare ops because it is covered by map_type */	return meta0->map_type == meta1->map_type &&		meta0->key_size == meta1->key_size &&		meta0->value_size == meta1->value_size &&		meta0->map_flags == meta1->map_flags &&		meta0->max_entries == meta1->max_entries;} void *bpf_map_fd_get_ptr(struct bpf_map *map,			 struct file *map_file /* not used */,			 int ufd){	struct bpf_map *inner_map;	struct fd f; 	f = fdget(ufd);	inner_map = __bpf_map_get(f);	if (IS_ERR(inner_map))		return inner_map; 	if (bpf_map_meta_equal(map->inner_map_meta, inner_map))		inner_map = bpf_map_inc(inner_map, false);	else		inner_map = ERR_PTR(-EINVAL); 	fdput(f);	return inner_map;} void bpf_map_fd_put_ptr(void *ptr){	/* ptr->ops->map_free() has to go through one	 * rcu grace period by itself.	 */	bpf_map_put(ptr);}